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We report novel supramolecular polymers, which possess a reversed viscosity/temperature profile. To this end, we developed a series of ditopic monomers featuring two self-complementary binding sites, either the guanidiniocarbonyl pyrrole carboxylic acid (GCP) or the aminopyridine carbonyl pyrrole carboxylic acid (ACP). At low temperatures, small cyclic structures are formed. However, at elevated temperatures, a ring–chain transformation leads to the formation of a supramolecular polymer. We demonstrate that this effect is dependent on the concentration of the solution and on the polarity of the solvent. This effect can counteract the loss of viscosity of the solvent at elevated temperatures, thus opening an application of our systems as viscosity index improvers (VIIs) in working fluids. This was tested for different motor oils and led to the identification of one compound as a promising VII.

Macrocycles with quaterthiophene subunits were obtained by cyclooligomerization by direct oxidative coupling of unsubstituted dithiophene moieties. The rings were closed with high selectivity by an α,β′-connection of the thiophenes as proven by NMR spectroscopy. The reaction of the precursor with terthiophene moieties yielded the symmetric α,α′-linked macrocycle in low yield together with various differently connected isomers. Blocking of the β-position of the half-rings yielded selectively the α,α′-linked macrocycle. Selected cyclothiophenes were investigated by scanning tunneling microscopy, which displayed the formation of highly ordered 2D crystalline monolayers.

Different types of torque signals have already been considered in the application interfaces documents of the powertrain domain [2, 3]. The torque scheme based on a figure from [2] is given in ➌. Open image in new window ➌ Powertrain torque signals When defining AUTOSAR compliant signals, the focus is initially set on their content. In addition to the signal content a data type for each signal needs to be defined. From the multitude of data types available, the interface between gearbox and engine uses primarily linear, discretised physical data types, states, status bits (flags) and status bit combinations to bit fields. The “Actual torque at clutch” signal may serve as an example. This signal has an existing AUTOSAR application interface definition, demanding a high resolution of 0.0625 Nm/bit and 16 bits size in the current specification. In addition to this, a generic and wide-spread description is provided. “Actual torque at clutch”, “Actual torque at clutch without transmission intervention”, and “Torque at clutch request without transmission intervention” are representations of this signal and are typically all exchanged between engine control unit and gearbox control unit. The engine as provider needs a detailed description of the content since all signals essentially influence the smooth and safe gearbox operation. This description must cover accuracy demands as well as required timing characteristics and tolerances.

Photoinduced charge separation in blends of organic materials of different electronic affinity and in organic donor-acceptor hybrids is a process of increasing importance for biological and artificial energy conversion and photovoltaics. Organic polymer solar cells are composed of an electron donor and an electron acceptor between which an electron transfer occurs after excitation by sunlight. Charge separation results in the formation of donor cation radicals and acceptor anion radicals. Here, we present our studies on a donor-acceptor hybrid molecule composed of a phenylene-bithiophene macrocycle used as a donor and a perylene bisimide acceptor. Using continuous wave EPR and modern pulsed EPR methodology in combination with light excitation, intermolecular as well as intramolecular charge separation has been observed. Light-induced charge separation observed upon selective excitation of either one of the chromophores indicates that both LUMO-based and HOMO-based electron transfer from donor to acceptor takes place. These experimental findings are corroborated by DFT calculations in which the HOMO of the donor-acceptor hybrid molecule is found at the phenylene-bithiophene macrocycle and the LUMO at the perylene bisimide.

Chemotherapeutic drugs kill cancer cells, but it is unclear why this happens in responding patients but not in non-responders. Proteomic profiles of patients with oesophageal adenocarcinoma may be helpful in predicting response and selecting more effective treatment strategies. In this study, pretherapeutic oesophageal adenocarcinoma biopsies were analysed for proteomic changes associated with response to chemotherapy by MALDI imaging mass spectrometry. Resulting candidate proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and investigated for functional relevance in vitro. Clinical impact was validated in pretherapeutic biopsies from an independent patient cohort. Studies on the incidence of these defects in other solid tumours were included. We discovered that clinical response to cisplatin correlated with pre-existing defects in the mitochondrial respiratory chain complexes of cancer cells, caused by loss of specific cytochrome c oxidase (COX) subunits. Knockdown of a COX protein altered chemosensitivity in vitro, increasing the propensity of cancer cells to undergo cell death following cisplatin treatment. In an independent validation, patients with reduced COX protein expression prior to treatment exhibited favourable clinical outcomes to chemotherapy, whereas tumours with unchanged COX expression were chemoresistant. In conclusion, previously undiscovered pre-existing defects in mitochondrial respiratory complexes cause cancer cells to become chemosensitive: mitochondrial defects lower the cells' threshold for undergoing cell death in response to cisplatin. By contrast, cancer cells with intact mitochondrial respiratory complexes are chemoresistant and have a high threshold for cisplatin-induced cell death. This connection between mitochondrial respiration and chemosensitivity is relevant to anticancer therapeutics that target the mitochondrial electron transport chain.

A route towards phenylene-thiophene macrocycles (IV) via oxidative thiophene coupling under pseudo-high dilution conditions is reported.

A route towards phenylene-bithiophene macrocycles via oxidative thiophene coupling under pseudo-high dilution conditions is reported. This method is applied to the synthesis of a shape-persistent thiophene macrocycle with extraannularly attached perylenebisimide moieties that forms supramolecular aggregates at the solid/liquid interface.